Centrifugal shot peening device



Jan. 27, 1970 J. ALoNso 3,491,563

CENTRIFUGAL SHOT PEENING DEVICE 5 Sheets-Sheet 1 Filedv April 30. 1968 'Jose /ono Jan. 27, 1970 J. ALoNsQ CENTRIFUGAL SHOT PEENING DEVICE Filed April 30, 1968 3 Sheets-Sheet 2 INV ENTOR /onso Jn; 27; 1970" J. ALONSO' f 3,491,563

CENTRIFUGAL SHOT PEENING DEVICE Filed April 30, 1968 I5 Sheets-Sheet 3 p w L v /98 HOPPER -/gg sfy f \v INVENTOR dws /.cwe

United States Patent O 3,491,563 CENTRIFUGAL SHOT PEENING DEVICE Jose Alonso, 23-24 Cambridge Road, Fair Lawn, NJ. 07410 Filed Apr. 30, 1968, Ser. No. 725,321 Int. Cl. BZlj 13/00 U.S. Cl. 72-53 10 Claims ABSTRACT OF THE DISCLOSURE- The disclosure describes a device containing an impeller driven by a motor. Shot balls or beads are fed into the device near the center of the impeller. The shot balls are accelerated centrfugally and are tangentially discharged from the device to impinge on a piece of Work being peened.

For successful operation such prior systems require air compressors, air hoses and other paraphernalia which are awkward to handle, diicult to control, expensive to install, and costly to operate. 'Ille present invention avoids these objections by providing a shot peening device which has a self-contained motor driving an impeller for imparting high controllable speeds to shot fed into the device.

One object of the invention is to provide a shot peening device having a motor driven impeller in a casing arranged to receive shot from a hopper and to discharge the shot at high speed tangentially from the casing.

A further object is to provide a shot peening device as described wherein the casing is lined with resilient, selflubricating shock resistant material to reduce impact and wear inside the case and wherein the impeller will be made of any metal such as aluminum or carbide steel.

For further comprehension of the invention and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings and to the appended claims in which the various novel features of the invention are more particularly Set forth.

In the accompanying drawings forming a material part of this disclosure:

FIGURE 1 is a perspective view of a shot peening device embodying the invention.

FIG. 2 is an enlarged vertical sectional view taken on line 2 2 of FIG. 1.

FIG. 3 is an exploded perspective view of parts of the device.

FIG. 4 and FIG. 5 are enlarged fragmentary sectional views taken on lines 4-4 of FIG. 3 and 5-5 of FIG. 3, respectively.

FIG. 6 is a reduced perspective view of an array of equipment employing shot peening devices according to the invention.

FIG. 7 is a fragmentary perspective view of another array of equipment employing the invention.

FIG. 8 is a vertical sectional view of a vibratory shot feeder employed in the array of FIG. 7.

FIG. 9 is a fragmentary sectional view taken on line 9-9 of FIG. 8.

ICC

Referring first to FIGS. l5, there is shown device 10 having a casing 12 including a tapered dished base 14 and cylindrical cover 16'. In the base is an electric motor 18 energized via an electric cable 20 passing through a grommet 22 at one side of the base. The motor has a central drive shaft 24 extending axially of cover 16. The cover has a circular top 25 and cylindrical wall 26. In top 25 is a centrally located bearing 28 which permits the outer end of shaft to rotate.

Interposed between radial annular flange 30 at the open top of the base and the bottom edge of wall 26 is a circular spacer plate 32. This plate is fitted with a central bearing 34 through which shaft 24 extends. Bolts 35 extend through holes 36, 37 in ilange 30 and plate 32. The bolts are seated in threaded holes 38 in cylindrical Wall 26 of the cover. The inner side of the top 25 of the cover and the inner side of wall 2.6 is lined with a tough, resilient liner 40. This liner is preferably made of a synthetic, self-lubricating elastomer such as polytetralluorethylene or the like.

Rotatably disposed inside the cover above plate 32 is an impeller 50. The impeller has a circular base plate 52. Integral with this plate is a plurality of L-shaped angle bars 54. The bars extend radially from a central hub 56 extending axially from and integral with base plate 52. The hub 56 has a slot 57 and bore 57' which receive key 53 and shaft 24 so that the Shaft turns the impeller. Radial channels C are defined between overchanging walls 55 and axially extending radial walls 56 of bars 54, and the base plate 52, see FIG. 5. All the channels are open at one side and at outer ends of the angle bars. The Walls 5-5, 56 of the angle bars and the upper side 59 of plate 52 are all coated with a resilient liner 60. The liner is made of tough, self-lubricating material like liner 40. Thus all channels are covered by liner 60.

Near its center, on top 25 of the cover is a nipple 62. Attached to this nipple by clamp 63 is a flexible pipe 64. Balls of shot 65 are fed through this pipe and into the tapered end 66 of .bore `68 in the nipple. The nipple is integral with top 25 of the cover. Hole 69 in liner 40 registers with bore 68 so that the shot 65 falls into the impeller 50 between the lined angle rbars and on to plate 52. An opening 70 is provided in one side of wall 26 of the cover. This opening registers with opening 71 in liner 40 and is coplanar with channels C. Integral with wall 25 is a tangentially extending nozzle 72 starting from opening 70 and providing communication between the interior of the cover and the exterior of the casing. A support bar 75 can be screwed into threaded bore 76 in wall 26 to extend radially therefrom, see FIG. 4.

FIG. 6 shows one example of a shot peening system 100 in which a plurality of shot peening devices 10 constructed as described in connection with FIGS. 1-5 above are provided. The devices 10 are supported by universal clamps 102 connecting bars 75 to extension bars 104 adjustably secured by clamps 106 to horizontal bar 108. Bar 108 is supported by walls 110 of a hook 120 in which the assembly is installed. A hopper 122 is supported above devices 10. It contains the shot 65 discharged from the several devices. This hopper has outlets 124 to which a plurality of flexible pipes 64 are connected by clamps 125. The electric cords or cables 20 of the several devices 10 are connected to an electric power supply box 126. A control 128 on this box can be adjusted to regulate the current or voltage applied to the motors in the several devices for setting the speed of the motors.

A turntable 130 is supported on a rotatable shaft 132 extending through inclined iioor 134 of the hood. A workpiece 136, in this instance a bowed spring of a vehicle, is mounted on the turntable and rotates with it. When the motors of the shot peening devices are turned on and shot 65 is released from the hopper, the shot is discharged at very high velocity from the nozzles 72 all aimed at the workpiece 136. As the workpiece turns it is smoothly hardened and smoothly polished by the impingin'g shot. The walls of the hood retain the discharge shot for reloading in the hopper and reuse. The discharged shot 65 collects in trough 134' of the floor 134i.

It will be noted that the resilient liners 40, 60 of the casing and the impeller prevent wear of the metal parts of the device 10. Furthermore, the smooth selflubricating lining of channels C permit the shot 65 to roll frictionlessly radially of the impeller and circumierentially1 of the cover to be discharged at very high velocity from the nozzle 72. The resilient liners also reduce operating noise considerably since they absorb the impact of shot striking the wall 26 and parts of the impeller as the shot drops into the casing and on the rotating impeller.

The metal parts of the casing can be made of lightweight aluminum. Thus the device 10 will have minimum weight and can easily be handled and supported. By making the metal parts of cast aluminum the device can be manufactured very economically. The device cari be made up in various sizes with diierent size motors for different applications.

In FIG. 7 is shown an array of equipment 100A in which shot peening device 10 is supported in an axially horizontal position by a horizontal bar 150 carried by iianged clamp plates 152 supported on spaced vertical posts 154 on iioor 156 of hood 160. Bolts 162 and nuts 164 on the clamp plates adjustably position bar 150 on the posts. An axially vertical funnel 166 has a bottom discharge nozzle 167 connected to nipple 62 through which shot 65 is fed to the device 10. Support bar 75 is secured by cross iitting 168 to bar 150. Screws 170, 172 in the fitting secure bar 75 in iitting 168 and secure the fitting on bar 150.

Shot 165 is dropped freely into the funnel from a vibratory gate or valve 180. The gate 180 has a tubular arm 182 secured by bolt 184 axially vertical discharge nozzle 186 of hopper 188 which contains the balls of shot 165; see FIG. 8. Arm 182 communicates with cylindrical housing 190 of the gate via a lateral opening 192. At the upper end of the housing is a solenoid 194 contained in a casing 196 on top of the housing. The solenoid is connected via cable 198 in parallel with cable 20 to a remote alternating current electrical power supp-iy. Thus when the motor of the device 10 is running the solenoid is energized. The solenoid has a reciprocatable verticai magnetic plunger 200. A coil spring 202 is mounted on the plunger and is engaged between cap 204 of the plunger and the top of the casing 196.

Secured to plunger 200 is a vertical rod 206 which terminates in a universal bali joint 208 engaged with ball 209 formed on top of a short rod 210; see F'iG. 9. Rod 210 is secured in the body of a resilient rubber or plastic ball 212. The ball 212 is located in and normally closes tapered throat 214 of housing 190. The lball 212 is sup- Vported in a self-aligning position in throat 214 by joint 208, 209 and by rods 206, 210, plunger 200 and spring 202. Normally arm 182 if lled with shot 165 which covers the top of ball 212 at throat 214. When the solenoid is energized by alternating current, the plunger and ball reciprocate vertically While the shot is fed past the ball 212 at throat 214 in the cylindrical bottom section 220 of the housing. A -funnel 224 is secured to the bottom of the bottom section 220. Nozzle 225 of funnel 224 is vertical and disposed above funnel 166. Thus the shot 165 drips gravitationally into the funnel 166 to keep it filled and thus supplies the device 10 with shot while both the solenoid 194 and motor of the device 10 are running.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and that various changes and modifications may be made within the scope of the invention as delined in the appended claims.

What is claimed is:

1. A shot peening device, comprising a hollow casing having a base and cover, means detachably connecting the base and cover together, an electric motor in the base, said cover having a circular top and cylindrical side wall, said motor having a drive shaft extending axially of the cover, a rotary impeller disposed in the cover, said impeller having a circular base plate with central hub keyed to said shaft so that the impeller is rotated by the shaft when the motor is running, said impeller having a plurality of angle bars integrally -ormed therewith and extending radially of the hub on the base plate, said angle bars deiining radially extending channels open at one side and at outer ends thereof for guiding balls of shot therealong, said cylindrical wall having a lateral opening, a nozzle integral with said cylindrical waii and extending from said opening tangentially of the said cylindrical wall to provide communication between the interior of the casing and the exterior thereof for discharging balls of shot from the casing, and a nipple integrally formed with the top of the cover and opening near the center thereof into the casing at a point between the hub and the p..- riphery of the base plate of the impeller, whereby balls of shot passing gravitationaliy into the casing through said nipple are guided along said channels under centriugal force of the rotating impeller to be discharged at high speed from saidnozzle.

2. A sho-t peening device as recited in claim 1, further comprising resilient linings covering interior walls of the casing exposed to the balls of shot passing through the casing, said linings serving to absorb impacts of the balls of shot to prevent Wear thereof and to reduce operating noise.

3. A shot peening device as recited in claim 2, wherein said linings are made of self-lubricating material to minimize friction and maximize speed of movement of the balls of shot along said channels and arc-und the inside of the cover.

4. A shot peening device as recited in claim 1, further comprising a bearing plate interposed between the base and cover, said bearing plate having bearing means receiving said shaft and supporting said impeller in the casing.

5. A shot peening device as recited in claim 4, further comprising a support. bar extending radially from the casing.

6. A shot peening device as recited in claim 1, wherein said cover has a threaded external radial bore in said cylindrical wall, and a support lbar detachably threaded in said radial bore and extending radially of the casing.

7. A shot peening device as recited in claim 3, further comprising a bearing plate interposed between the base and cover, said bearing plate having bearing means receiving said shaft and supporting said impeller in the casing.

8. A shot peening device as recited in claim 6, wherein I said threaded external radial bore in said cylindrical Wall is in said cover.

9. A shot peening device as recited in claim 8, wherein said casing is made of metal and the impeller of the most resistent carbide material or steel with resilient lining covering.

10. A shot peening device as recited in claim 8, wherein the casing is disposed in an axially horizontal position; an axially vertical funnel connected to said nipple for feeding shot into the casing; a hopper containing said shot disposed above said funnel; and a solenoid operated 5 6 gate valve supported by the hopper above the funnel and 2,422,786 6/1947 Keefer 51-9 arranged to discharge the shot from the hopper into the 2,532,136 11/ 1950 Zahn 51-9 funnel when the motor is running to keep the funnel lled with shot which ows gravitationally into the casing FOREIGN PATENTS through the nipple. 5 699,261 12/1964 Canada.

References Examiner UNITED STATES PATENTS G. P. CROSBY, Assistant Examiner 2,263,321 11/1941 Unger 51-9 10 U'S. C1. X R

2,376,639 5/1945 Unger 29-90 51-9, 319 

